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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        // 外层打印行数
        for (let i = 1; i <= 5; i++) {
            // 里层循环控制列数（几个心心）
            for (let j=1; j <= i; j++) {
                document.write('♥')
            }
            document.write('<br>')
        }

        // 换行
    </script>
</body>

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